JAKOBSHAVN, GREENLAND — A new study published in the Proceedings of the National Academy of Sciences of the U.S. claims that the massive Greenland ice sheet is on the brink of a major tipping point. <br /><br />The study's authors say enough ice to raise the global sea level by more than a meter is probably already doomed to melt from Greenland in the next few decades. Here are the details:<br /><br />The Guardian reports that a new study of the ice-sheet heights and melting rates in Greenland's Jakobshavn basin shows that the Greenland ice sheet is on the brink of a major tipping point. <br /><br />Rising temperatures caused by the climate crisis have already seen trillions of tons of Greenland's ice pour into the ocean. <br /><br />Melting its ice sheet completely would eventually raise the global sea level by seven meters. <br /><br />The prime suspect for this surge in melting in Greenland is a vicious circle in which melting lowers the height of the ice sheet, exposing it to the warmer air found at lower altitudes, which causes further melting. <br /><br />Study co-author Niklas Boers says the findings show destabilisation of this ice sheet is under way, and might already have passed the tipping point. <br /><br />Boers said the findings suggest there will be substantially increased melting in the near future. <br /><br />Ice equivalent to one to two metres of sea level rise was probably already doomed to melt, though this would take centuries, and melting the whole ice sheet would take a millennium.<br /><br />Scientists say any large-scale melting of the Greenland ice sheet would have long-term global consequences, beyond rising sea levels. <br /><br />It could halt the Gulf Stream ocean current, with potential knock-on effects on the Amazon rainforest and tropical monsoons.
